1. Field of the Invention
The present invention relates to a paper cutting device provided in a facsimile machine, copier, printer, or the like for cutting paper discharged from a roll at a predetermined length, and more particularly, to a paper cutting device including an elongated stationary cutter and a movable cutter which is movable along the stationary cutter to thereby cut the paper.
2. Description of the Related Art
Conventional copiers, printers, facsimile machines and the like include a paper cutting device for cutting a paper discharged from a roll page by page. A conventional paper cutting device is illustrated in FIG. 1. Such a device includes an elongated stationary cutter 21 having a stationary cutting edge and a movable cutter 22 having a movable cutting edge and being movable along the stationary cutter while being urged thereagainst so that the cutting edges cooperate to cut the paper. Specifically, a rotary cutting wheel 22 is used as the movable cutter and is positioned so that its peripheral cutting edge slightly overlaps the cutting edge of the stationary cutter 21 thereby cutting the paper as it is discharged from the roll.
The cutting wheel 22 is rotatably mounted to a carriage 23 which is movable on and along a guide rail 24a of an elongated guide plate 24 disposed in parallel to the stationary cutter 23. There is a narrow gap 25 between the elongated guide plate 24 and the stationary cutter 21 in which the paper, discharged from the roll, is inserted to hold the paper while the cutting wheel 22 is moved along the stationary cutter 21.
In order to move the cutting wheel along the guide rail 24a, the carriage 23 is fixed to a wire 27 which is disposed between pulleys 28a and 28b. The pulley 28a is coupled to a motor 29 to transmit a rotation force from the motor 29 to the wire 27. A frame 26 holds the stationary cutter 21, guide plate 24, pulleys 28a, 28b and motor 29, as illustrated in FIG. 1.
The paper is cut in the following manner. As noted above, the paper 10 is inserted into the gap 25 from the back of the frame 26 so that the paper is retained therein during a cutting operation. When the cutting wheel carriage 23 moves from one end of the guide rail 24a to the other end, the cutting wheel 22 in cooperation with the stationary cutter 21 cuts the paper 10.
FIG. 2 shows a printing mechanism of a facsimile receiver which uses the conventional paper cutting device of FIG. 1. A thermal sensing paper roll 10a is disposed in a case 41 which is fixed on a base 40. A cover 42 is located over the case 41. A platen roller 44 is coupled to the cover 42 and contacts a thermal head 43 with the paper disposed therebetween so as to record information on the paper 10 discharged from the thermal sensing paper roll 10a. During the printing operation, the platen roller 44 rotates to transmit the paper 10 via paper guide plates 45 into the gap 25 defined by the stationary cutter 22 and the guide plate 24 and the paper is cut, as shown in FIG. 3.
The problem associated with such an arrangement is that when a paper jam occurs in the narrow gap 25, it is extremely difficult to remove the jammed portion of the paper. Furthermore, when a new sheet is installed in the printer or the like, it is difficult and time consuming to hand feed the end of the paper through the narrow gap by hand or using a feed roller.
In more detail, when the paper roll 10a is set on the case 41 after removing the cover 42, the paper 10 has to be inserted between the guide plates 45 and then fed into the gap 25. However, when feeding the paper, the end of the paper 10 is sometimes obstructed at the entrance of the gap 25 because the gap 25 is too narrow. Moreover, when the paper jams in the gap 25, it is difficult to remove the jammed paper from the gap. On the other hand, if the gap 25 is widened in an effort to overcome the above problems associated with inserting the paper and unjamming the paper, the paper cannot be cut properly because the paper 10 floats and tends to curl in the gap during cutting, which causes the paper to jam.